1.Put a piece of material you want to make a project with in the guide where it feels and fits the way you want pieces to fit together. You will need to remove any masking that came on your product in the small section that you measure, usually a corner. If you will be putting masking or 3M adhesive on parts of your material, measure the material before applying. After measuring, you will find the size your slot needs to be in the design file itself. Use the exact engraved size measurement that is marked on the fit guide in your design - to 0.001 of variation accuracy (1000th of an inch). This will ensure that the design will result in the proper size gap that you need for a perfect product, every time. Using a caliper only tells you part of the story as putting that size into your design will result in items that do not fit together correctly. By making this file on each of your laser cutters, it will be accurate to your machine and material, specifically.